1/*	$NetBSD: kex.h,v 1.5 2011/07/25 03:03:10 christos Exp $	*/
2/* $OpenBSD: kex.h,v 1.52 2010/09/22 05:01:29 djm Exp $ */
3
4/*
5 * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27#ifndef KEX_H
28#define KEX_H
29
30#include <openssl/evp.h>
31#include <openssl/hmac.h>
32#include <openssl/ec.h>
33
34#define KEX_COOKIE_LEN	16
35
36#define	KEX_DH1			"diffie-hellman-group1-sha1"
37#define	KEX_DH14		"diffie-hellman-group14-sha1"
38#define	KEX_DHGEX_SHA1		"diffie-hellman-group-exchange-sha1"
39#define	KEX_DHGEX_SHA256	"diffie-hellman-group-exchange-sha256"
40#define	KEX_RESUME		"resume@appgate.com"
41/* The following represents the family of ECDH methods */
42#define	KEX_ECDH_SHA2_STEM	"ecdh-sha2-"
43
44#define COMP_NONE	0
45#define COMP_ZLIB	1
46#define COMP_DELAYED	2
47
48enum kex_init_proposals {
49	PROPOSAL_KEX_ALGS,
50	PROPOSAL_SERVER_HOST_KEY_ALGS,
51	PROPOSAL_ENC_ALGS_CTOS,
52	PROPOSAL_ENC_ALGS_STOC,
53	PROPOSAL_MAC_ALGS_CTOS,
54	PROPOSAL_MAC_ALGS_STOC,
55	PROPOSAL_COMP_ALGS_CTOS,
56	PROPOSAL_COMP_ALGS_STOC,
57	PROPOSAL_LANG_CTOS,
58	PROPOSAL_LANG_STOC,
59	PROPOSAL_MAX
60};
61
62enum kex_modes {
63	MODE_IN,
64	MODE_OUT,
65	MODE_MAX
66};
67
68enum kex_exchange {
69	KEX_DH_GRP1_SHA1,
70	KEX_DH_GRP14_SHA1,
71	KEX_DH_GEX_SHA1,
72	KEX_DH_GEX_SHA256,
73	KEX_ECDH_SHA2,
74	KEX_MAX
75};
76
77#define KEX_INIT_SENT	0x0001
78
79typedef struct Kex Kex;
80typedef struct Mac Mac;
81typedef struct Comp Comp;
82typedef struct Enc Enc;
83typedef struct Newkeys Newkeys;
84
85struct Enc {
86	char	*name;
87	Cipher	*cipher;
88	int	enabled;
89	u_int	key_len;
90	u_int	block_size;
91	u_char	*key;
92	u_char	*iv;
93};
94struct Mac {
95	char	*name;
96	int	enabled;
97	u_int	mac_len;
98	u_char	*key;
99	u_int	key_len;
100	int	type;
101	const EVP_MD	*evp_md;
102	HMAC_CTX	evp_ctx;
103	struct umac_ctx *umac_ctx;
104};
105struct Comp {
106	int	type;
107	int	enabled;
108	char	*name;
109};
110struct Newkeys {
111	Enc	enc;
112	Mac	mac;
113	Comp	comp;
114};
115struct Kex {
116	u_char	*session_id;
117	u_int	session_id_len;
118	Newkeys	*newkeys[MODE_MAX];
119	u_int	we_need;
120	int	server;
121	char	*name;
122	int	hostkey_type;
123	int	kex_type;
124	int	roaming;
125	Buffer	my;
126	Buffer	peer;
127	sig_atomic_t done;
128	int	flags;
129	const EVP_MD *evp_md;
130	char	*client_version_string;
131	char	*server_version_string;
132	int	(*verify_host_key)(Key *);
133	Key	*(*load_host_public_key)(int);
134	Key	*(*load_host_private_key)(int);
135	int	(*host_key_index)(Key *);
136	void	(*kex[KEX_MAX])(Kex *);
137};
138
139void	 kex_prop2buf(Buffer *, const char *proposal[PROPOSAL_MAX]);
140
141int	 kex_names_valid(const char *);
142
143Kex	*kex_setup(const char *[PROPOSAL_MAX]);
144void	 kex_finish(Kex *);
145
146void	 kex_send_kexinit(Kex *);
147void	 kex_input_kexinit(int, u_int32_t, void *);
148void	 kex_derive_keys(Kex *, u_char *, u_int, BIGNUM *);
149
150Newkeys *kex_get_newkeys(int);
151
152void	 kexdh_client(Kex *);
153void	 kexdh_server(Kex *);
154void	 kexgex_client(Kex *);
155void	 kexgex_server(Kex *);
156void	 kexecdh_client(Kex *);
157void	 kexecdh_server(Kex *);
158
159void
160kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
161    BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
162void
163kexgex_hash(const EVP_MD *, char *, char *, char *, int, char *,
164    int, u_char *, int, int, int, int, BIGNUM *, BIGNUM *, BIGNUM *,
165    BIGNUM *, BIGNUM *, u_char **, u_int *);
166void
167kex_ecdh_hash(const EVP_MD *, const EC_GROUP *, char *, char *, char *, int,
168    char *, int, u_char *, int, const EC_POINT *, const EC_POINT *,
169    const BIGNUM *, u_char **, u_int *);
170
171int	kex_ecdh_name_to_nid(const char *);
172const EVP_MD *kex_ecdh_name_to_evpmd(const char *);
173
174void
175derive_ssh1_session_id(BIGNUM *, BIGNUM *, u_int8_t[8], u_int8_t[16]);
176
177#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
178void	dump_digest(char *, u_char *, int);
179#endif
180
181#endif
182